On construction sites, concrete can be supplied by three ways: the first is that workers mix cement, sand, gravel and water on a board or plate manually using appropriate tools, for example, a shovel the second is that the concrete is prepared by a cement mixer and then it is poured into a suitable apparatus, for example, a wheelbarrow whereby the concrete can to be delivered to a casting position and the third is that the concrete is pre-prepared in a mixing plant and transported to the construction site by mixer lorries and finally delivered to the casting position by concrete delivery pumps and pipes.
All of the above-mentioned ways to provide concrete have their respective disadvantages. In particular, the first and second ways are laborious and have a low efficiency of operation, and the third, although more efficient to operate, requires a high expenditure for the equipment.